"Obviously there are immediate pressures with cuts and jobs disappearing, wards closing in too many trusts," he said.

"People not able to find jobs when they've completed their training - nurses, physiotherapists. So all of those kinds of problems.

"But (there is) a feeling that the direction of policy is just not right. The privatisation, the fragmentation of the NHS is really threatening the whole integrity of the service. I think that's what people are saying today."

Dr Peter Carter, of the Royal College of Nursing, said nurses were "angry and upset" over a number of issues.

He told BBC News 24: "Over the last year or so nurses have seen jobs frozen, redundancies, services closed, wards closed, student nurses not being able to get jobs on finishing their training, which is a pretty depressing state of affairs.

"And then you've had on Thursday the announcement by the government that they were not going to fully implement the recommendations of the pay review body that nurses should get 2.5%.

"And so it's a combination of both of these things have led to an extremely frustrated nursing workforce."

Staff 'signed up'

Health Minister Rosie Winterton said unions and staff signed up to the principles of the NHS Plan, which sets out reforms over 10 years.

She said: "If we know that change will deliver better quality care and better value for money for taxpayers, then standing still is simply not an option."

There must be a different approach... it is about reform, it is about introducing elements of choice and competition

Andrew Haldenby, Reform think-tank

She added that nine out of 10 patients rated the care they received as excellent, very good or good.

Andrew Haldenby, director of Reform, a think-tank calling for new solutions for the health service, told BBC's PM programme a huge amount of money had been put into the NHS in an "indiscriminate" way - leading to more staff and higher salaries and therefore higher costs.

"That now is making the service almost unaffordable, and that is why we are seeing cutbacks - according to one survey this week - in three-quarters of all NHS trusts," he said.

"There must be a different approach... it is about reform, it is about introducing elements of choice and competition."

Ministers were going in the right direction but reform was not being driven through quickly enough, he added.